CSS (Cascading Style Sheets)
Definition
A stylesheet language used to describe the visual presentation and layout of HTML documents, controlling colors, fonts, spacing, and responsive design.
Cascading Style Sheets is the language used to style and layout web pages. It controls how HTML elements appear on screen, in print, or in other media. CSS separates content (HTML) from presentation (styling), making websites more maintainable and accessible.
Modern CSS includes powerful layout systems like Flexbox (one-dimensional layouts) and Grid (two-dimensional layouts), as well as custom properties (variables), animations, transitions, media queries for responsive design, and newer features like container queries and the :has() selector.
CSS follows the cascade: when multiple rules apply to the same element, specificity, source order, and importance determine which styles win. Understanding the cascade, the box model, and positioning contexts is fundamental to writing predictable, maintainable stylesheets.
Related Calculators
Related Terms
HTML (HyperText Markup Language)
techThe standard markup language for creating web pages, defining the structure and content of a page using elements represented by tags.
DOM (Document Object Model)
techA programming interface for web documents that represents the page structure as a tree of objects, allowing programs to change document structure, style, and content.
CDN (Content Delivery Network)
techA geographically distributed network of servers that delivers web content to users from the nearest location, reducing latency and improving load times.
URL (Uniform Resource Locator)
techA web address that specifies the location of a resource on the internet, including the protocol, domain name, path, and optional parameters.
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